Magnetic microrobot control using an adaptive fuzzy sliding-mode method

The magnetic medical microrobots are influenced by diverse factors such as the medium, the geometry of the microrobot, and the imaging procedure. It is worth noting that the size limitations make it difficult or even impossible to obtain reliable physical properties of the system. In this research, to achieve a precise microrobot control using minimum knowledge about the system, an Adaptive Fuzzy Sliding-Mode Control (AFSMC) scheme is designed for the motion control problem of the magnetically actuated microrobots in presence of input saturation constraint. The AFSMC input consists of a fuzzy system designed to approximate an unknown nonlinear dynamical system and a robust term considered for mismatch compensation. According to the designed adaptation laws, the asymptotic stability is proved based on the Lyapunov theorem and Barbalat's lemma. In order to evaluate the effectiveness of the proposed method, a comparative simulation study is conducted

Climbing and Walking Robots

Nowadays robotics is one of the most dynamic fields of scientific researches. The shift of robotics researches from manufacturing to services applications is clear. During the last decades interest in studying climbing and walking robots has been increased. This increasing interest has been in many areas that most important ones of them are: mechanics, electronics, medical engineering, cybernetics, controls, and computers. Today’s climbing and walking robots are a combination of manipulative, perceptive, communicative, and cognitive abilities and they are capable of performing many tasks in industrial and non- industrial environments. Surveillance, planetary exploration, emergence rescue operations, reconnaissance, petrochemical applications, construction, entertainment, personal services, intervention in severe environments, transportation, medical and etc are some applications from a very diverse application fields of climbing and walking robots. By great progress in this area of robotics it is anticipated that next generation climbing and walking robots will enhance lives and will change the way the human works, thinks and makes decisions. This book presents the state of the art achievments, recent developments, applications and future challenges of climbing and walking robots. These are presented in 24 chapters by authors throughtot the world The book serves as a reference especially for the researchers who are interested in mobile robots. It also is useful for industrial engineers and graduate students in advanced study

Uncalibrated Visual Servo Control of Magnetically Actuated Microrobots in a Fluid Environment

Microrobots have a number of potential applications for micromanipulation and assembly, but also offer challenges in power and control. This paper describes an uncalibrated vision-based control system for magnetically actuated microrobots operating untethered at the interface between two immiscible fluids. The microrobots are 20 μm thick and approximately 100–200 μm in lateral dimension. Several different robot shapes are investigated. The robots and fluid are in a 20 × 20 × 15 mm vial placed at the center of four electromagnets. Pulse width modulation of the electromagnet currents is used to control robot speed and direction. Given a desired position, a controller based on recursive least square estimation drives the microrobot to the goal without a priori knowledge of system parameters such as drag coefficients or intrinsic and extrinsic camera parameters. Results are verified experimentally using a variety of microrobot shapes and system configurations